Name

UnixFromLine

Synopsis

The UnixFromLine option replaces the pre-V8.7 $l macro. It has two functions:

  • It defines the look of the five character "From " header line needed by UUCP software.

  • It defines the format of the line that is used to separate one message from another in a file of many mail messages.

The forms of the UnixFromLine option and $l macro are as follows:

Dlformat                        configuration file (V8.6 and earlier) 
O UnixFromLine=format           configuration file (V8.7 and later) 
-OUnixFromLine=format           command line (V8.7 and later) 
define(`confFROM_LINE',`format') mc configuration (V8.7 and later) 

The format is of type string. Under V8.6 and earlier there was no default for format, so the $l macro always had to be defined. Beginning with V8.7, sendmail first checks to see if the UnixFromLine option was defined and uses that value if it was. Otherwise, it checks to see whether the level of the configuration file is 6 or less. If it is and if the $l macro was defined, it uses that value. Otherwise, it uses the default:

From $g  $d

Here, $g ($g) holds the sender’s address relative to recipient, and $d ($d) holds as its value the current date in Unix ctime(3) format.

The UnixFromLine option is not safe. If specified from the command line, it can cause sendmail to relinquish its special privileges.

UnixFromLine in UUCP software

UUCP software requires all messages to begin with a header line that looks like this:

From sender   date  remote from <host>

The sendmail program prefixes such a line ...

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